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All rattles still completely gone since I had to have the front farings and headlight assembly replaced.

It took about 500km for the rattle to develop in the beginning so I'm hoping it doesn't return again after the new pieces get a chance to loosen up with vibrations.
 

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I had my first service done today and was told that the rattle is in the engine and Honda is aware of the problem. Honda told my dealer it is the rocker arms.
I think this is what you say to the customer instead of 'we dont know'.

Wiggly body work can make a lot of strange noises, but since it does not move, it gets its sound from what does move, the engine. And the bodywork becomes a speaker.
 

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I had a rattling too... didn't take me very long to realize it was my keys. Still get it every so often, but I remember what it is, move my keys and it goes away.
FYI: Valve clearance spec is Intake: 0.16 +/- 0.03mm
Exhaust: 0.27 +/- 0.03mm
 

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I had a noise but found it was the 2 bolts in the back of the bike for the chain adjustment. tightened them up and it was gone. I was actually able to move them with my fingers before the fix
 

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The front fairings and headlight assembly were changed on my bike. No rattles since them. Sounds great after 16,000km with them.

If you have the skill and knowhow strip it down to the headlight assembly and check everything in and around there is proper tight. That would be my reco.

Mine begun after about 500km so I'm hoping it doesn't start again, but if it does it will be the first place I send my mechanics to check out, it having been solved by replacing it.
 

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Had the bike in for the 600 mile valve check - within spec -no adjustments made. It rattled before the service and it's still rattling after the service. After the valve check I was able to demonstrate the noise to the dealer right there in his service bay, standing still, in neutral, revving to 5,00rpm. They acknowledged that the noise was there but had no explanation for it. They didn't say so outright but inferred that we'll have to wait for the noise to get much worse or for more people to complain about it before Honda will act on it. Their apparent reluctance to go looking for the cause indicates to me that local dealers can't get Honda to cover, under warranty, any diagnostic time they spend looking for the noise. We'll have to wait for Honda to find the problem and hopefully we'll see a "TSB" which will allow local dealers to fix the problem under warranty.
 

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Thankfully, my bike (at 2500km) doesn't make this noise. That being said, usually 'Marbles in a can' noise is cam-chain tensioner. Anybody check that?
 

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Just to add to this whole topic. My bike had 0 engine rattles for the first few months that I had it. It broke down on me the other day on the way to school. Got it back from the mechanic and now there is engine rattles throughout all rpms and gets worse towards 5500...

Kinda sketched out to drive it.
 

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At least someone is easy going

Don't waste your breath, they are not going to do anything unless it's broken. You have to try and break it. It's the only way, I'm not trying to be rude. But, if there is something wrong with the motor, then it will not last and they will have to fix it under warranty. Just to say 'what about this random noise,' they are not going to give you any information.

If I hear something rattle, I just figure it's some plastic. If I think my bike is making a funny noise, I just go faster. Basically, I tried to break it, but at 3800 miles it runs better than new and I expect it will get better still.

Don't worry about your rattle. Enjoy your bike, if it breaks, they'll fix it.
I like that
 

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So you hear it when revving in neutral or you ride around with no helmet?

If you can't hear it with a helmet on you haven't got the same 5-6k rpm rattle (marbles in a blender) that I had.
Yes i have the same rattle everyone has 5-6000 rpm some days i ride with no halmet if i'm in town. And yes you can hear it free reving it.
 

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I just discovered that I can replicate my rattle with the engine off.
I can't say if my rattle is the same but if I vibrate my left fairing with just my hand I get the same noise that I get on the road at around 5,5K rpm.

I also discovered that on the left side of my bike the top fairing, the little guy that sits right on top of the side fairing has a crappy plastic pop rivet that is reallly loose. It literally fell out when I touched it. The one on the right is nice & tight and I get no noise no matter how hard I shake the fairing. So it's off to the dealer tomorrow to order some pop rivets. I have the feeling I'll be needing a few extras down the road.
 

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OK, here are my findings on the noise issue. Having decided that the PAIR valve was probably the culprit and reading on the 'net that lots of motorcycles have noise associated with this thing, I decided to take mine apart to see what I could see.

In the attached pictures, I think you will notice the marks on the screen that, to me, indicate that it has been bouncing around in there. The screen is supported in three places when mounted and you can see that one of the places looks reasonable but two of them are very shiny and look a bit abraded. The reed valve itself seems well made with lots of attention to reducing noise; neoprene surfaces everywhere.

To address this, I did two things. The first was to carefully bend the screen so that it would 'load up' as the cover was tightened and ensure that the screen would be held as the parts heated up. The second was to put a very slight twist in the reed valve limiter. This is a rather old trick to have the reed twist slightly as it is sucked against the limit and layout quietly rather than smack it all at once.

With these two changes, things improved a great deal but I took it out again and made one more modification. I removed the reed itself and curved it so that it did not smack the port but rather laid out smoothly. Again, this is a rather old trick of my profession. The curve must be very smooth and such that the reed in rest position is about 1/2 way between the port and the limit. Do not use pliers for this; fingers maybe but I used a burnishing tool to 'pull' the curve into it.

Putting it back together, it is very quiet now and I have been running for a few days and find myself using the 5k rpm range a lot more. Previously, I tended to avoid it because of the rattle. I have also noticed that the engine appears much smoother and quieter on startup and I tend to just go rather than warm it up.

Since this issue has been a problem for some bikes and not others, I an inclined to think that the shield rattling around inside is probably the worst offender. Since this is held in place by the valve, a change to either of them would affect the fit.

It is possible to just remove the thing and block the port but that would be increasing the unburnt hydrocarbons in the exhaust. Since I bought the bike to contribute less pollution (among other things), I would like a solution that keeps the valve in operation.

It is very easy to work on the valve; you remove the fairings and lower the radiator and remove two bolts and a hose.

I hope you find this useful.

Thanks, I have never worked on an engine but after reading this (and many other threads) I am convinced it is important. I think im going to get a service manual first but would definitely like to attempt what you've done here. Ill let you know how it goes or if i run into any probs
 
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